The present invention relates to a plug-and-socket connector for data transmission cables with a plurality of electrical conductors which, for example, are twisted in pairs. The invention in particular relates to a plug-and-socket connector according to an international standard, for example the standard IEC 60603-7 (called RJ45 for short) or IEC 61076-2-xx (round plug-and-socket connector for the low voltage range, represented here by: M12).
Data transmission systems with a plurality of electrical conductors, in particular of the type with conductors twisted in pairs, are assuming greater and greater significance. It is particularly in the field of the office that the structured building-wiring has had much success. This, amongst other things, is due to standardized plug-and-socket connections.
The increasing digitalization in all fields of everyday life leads to the fact that plug-and-socket connections, also originally designed for the telecommunications- and office field, for example of the type RJ45, are increasingly also used in other fields of application. The great success which structured building-wiring has in the field of the office should also be exploited in other fields of application. Therefore, the field of industry, of building automation and the audio field are to be specifically mentioned.
These new fields of application entail new demands on the product. Two new demands on an RJ45 plug in these fields are, for example, the wiring ability on location without special tools, or the use with different, more robust cables (conductor diameter, construction, size etc.) than are usual in the office field. These plugs, however, should simultaneously also be very compact, so that they remain compatible with existing end apparatus.
In order to be able to ensure a sufficient wiring comfort and a broad field of application, known and commonly used cut-and-clamp technology is particularly suitable for the connection technology. With this connection technology, insulation displacement connectors or insulation displacement contacts (IDCs) are used. Connection blocks with IDCs have been known for some time, for example from EP 0 671 780. These known IDC blocks, however, do not fulfill the demands with regard to the compactness.
Of the existing RJ45 plug-and-socket systems, connection techniques are known which comprise IDCs in the direction of the longitudinal axis of the plug. With these plug-and-socket systems, the connection conductors are introduced into the IDCs by way of a movement in the axial direction, i.e. in the insert direction of the RJ45 plug. Usually, a wiring piece is applied at the same time in which the conductors are previously laid, and which for contacting, is moved relative to the plug housing in the axial direction. Such a wiring piece usually has a central hole through which the cable is led. Thereafter, the conductors are held in the wiring piece, bent at an angle radially to the cable direction, and are presented with the IDCs for contacting (for this, see e.g. EP 0 899 827, DE 102 58 725, U.S. Pat. No. 6,752,647). These connection techniques, although having the potential to fulfill the requirements with regard to size are, however, not suitable with regard to handling ability and stability for covering the total cable cross-sectional range required in the new fields of application.
For this reason, it would be desirable to have a plug-and-socket connection part at one's disposal, which similar to the original IDCs, is radially wired, but which may be designed in a more space-saving manner by way of wiring on both sides. Such a solution with a single-piece wiring block is known from EP 991 149. The disadvantage with such a single-piece wiring block is the fact that the required individual conductor mountings in the IDC chambers must be broken or weakened, so that the IDCs on manufacture of the connection block may be applied at all into chambers envisaged for this. The consequence of this is that either a clean individual conductor strain relief is no longer guaranteed, or that for an adequately large wall thickness, the distances between the individual conductors (also called cable cores or stranded wire conductors or wires) must be selected so large that the connection block no longer meets the initially posed demands with regard to the dimensioning.